An automatic analysis device has a washing mechanism and a washing tank which wash a reaction container for mixing a sample and a reagent or a probe used in dispensing by using water or a predetermined detergent, immediately before use. The automatic analysis device aims to prevent analysis accuracy from being degraded due to dirt adhering to the reaction container or the probe. However, blood or urine as an analysis target sample contains proteins and lipids. Thus, the automatic analysis device is in a situation where the dirt is likely to adhere to the reaction container or the probe. In addition, since the reaction container or the probe is repeatedly used, it is difficult to remove the adhering dirt by only performing washing immediately before.
Therefore, for example, the dirt adhering to the reaction container or the probe is removed by periodically performing maintenance in which the inside of the reaction container or the probe is soaked in a high concentration detergent for a fixed period of time. For example, PTL 1 (JP-A-2008-281454) discloses that the reaction container or the probe is soaked and washed by utilizing a period of time while a device is not used for analysis, such as during standby.